Intermittent driving mechanism for motion-picture machines.



N. POWER. 4

INTERMITTENT DRIVING MEOHANISM FOR MOTION PICTURE MAGHINES.

APPLICATION FILED 0GT.4, 1910.

Patented Feb. 23, 1915.

wi li'n may S 14 00 Whoa I 35 E1 0 011 M Z W a H s lJNTTED STATES PATENT OFFICE.

llIGI- JGLAS. POT ER, Q1 BROGKLYN, NEW YORK, ASSIGNOR TO NICHOLAS POWER.- GOMPANY, OF YORK, N. Y., A CORPORATION OF DELAW'ARE.

INTERMITTENT DRIVING MECHANISM FORibIOTION-IICTURE MACHINES.

Specification of Letters Patent.

Patented Feb. 23, 1915.

' Application filed October 4, 1910. Serial No. 585,202.

To all whom it may concern Be it known that I, NICHOLAS Pown'n, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of-llew York, with post-office address at No. 888 Jefferson avenue, have invented certain new and useful Improvements in Intermittent Drivin hlechanism for Motion-Picture Machines, or which the following is a specification.

This invention relates to projecting apparatus, and more particularly to apparatus for projecting moving pictures.

The primary object of the invention is to improve the mechanism, by means of which an intermittent movement is imparted to the strip, or film, bearing the pictures to be projected.

A further object of the invention is to improve the projecting apparatus for moving pictures with respect to the reduction of the wear upon the film in its passage through the apparatus.

Other objects of the invention will occur in the course of the following description in which reference is made to the accompanying drawing in which is illustrated a single embodiment of the invention and in which the corresponding parts are designated by similar characters of reference in the several views.

Figure 1 is a horizontal section through the intermittent movement showing the relation of the driving shaft and driven shaft carrying the feed sprocket; Fig. 2 is an end view from the left of Fig. 1 with the outer portion of the casing removed; and Fig. 3 is a detail. view showingthe parts in different positions from that shown in Fig. 2.

I have shown my improved intermittent driving gear as applied to a feed. sprocket 6 for feeding the fi m in a moving picture machine past the projecting lens in front of which the successive pictures are momentarily brought to rest for projection on the screen.

The mechanism consists of two members 18 and 19, the former comprising a cam 18 of approximately diamond shape, and the latter consisting preferably of a cross,-h aving four arms 20, arranged at right angles to each other, and each bearing near its outer end a pin 21. The cam member 18 is mount-- ed upon a heavy shaft 22, to which motion is imparted by any suitable means, as for instance, a suitable gear as indicated in Fig. 1. The driven member 19 is mounted on a spindle 11 which also has bearings in the carriage and is arranged just below the main or cam shaft. The cam member 18 is preferably cut from a single block of steel and comprises in addition to the cam proper 18 a locking ring 26, which is concentric with the shaft on which the member 17 is mounted. This looking ring is of such width that it will just pass between the pin or studs on the driven member 19, two studs lying within the ring and two without. The ring is incomplete and the ends are spaced from the sides of the cam proper, as she in 6. The ends of the ring are so shaped that passages 27, of a suitable width to just permit the studs on the driven member to pass therethrough are left between the ends of the ring and the sides of the cam proper 18. lVhen the apparatus is in operation the cam member is driven at a speed ranging from about 800 revolutions per minute to a speed of 1200 or more revolutions per minute, and, as considerable energy is required to impart the intermittent rotation to the driven member 19, its spindle and the sprocket mounted thereon, the member 18, and the spindle upon which it is carried are made quite massive so as to insure rigidity and resistance to wear. Itis also preferable that the cam member be made of tool steel and adapted to be tempered, and that the cam proper at least be tempered so as to withstand Wear and shock.

The spindle 11 is journaled in slightly eccentric bushings 28, 29, the former being small in diameter and the latter relatively large. It will be noted on comparison of the diameters of the bushing 29 and the sprocket carried on the spindle 11, that the bushing is of the larger diameter. The purpose of this construction is to permit the removal of the spindle and the sprocket from its position in the framing carriage without detaching the sprocket from the spindle. This is easily accomplished 'by merelv loosening the screw which holds the bushing in place and sliding the bushing, spindle and sprocket through. the opening in the framing carriage provided for the bushing.

To insure long service of the mechanism for imparting intermittent movement to the parts, they are inclosed in a dust-proof casing consisting of an inner part, 30, and

an outer p art, ,31. The former is cast integral with the framing carriage and the latter is in the form of a cap which is secured to the iiiner member or the casing by means of screws 32.

It will be noted that the general outline I of the casing iscircular, but a smaller cavity orpocket is formedatthe lower part there'- of to provide clearance for; the turning of of oilinto the casing, which is objectionable because of its tendency'to workfiits way through the bearings. for the spindles which extendrinto'the casing, and? soqescapeoon to the film as itipasses through; the apparatus. :Qvving to the peculiar construction ofthe members 18 andl 19. by which intermittent movement is imparted to, the sprocket 6 movement isi'mparted to,the sprocket during only about of the time? of rotatibn of the driving membert18 and theintelmittentspindle 11 is held perfectly stillduningthe remainder of; the rotation of the driving member 18,, because during fthisftimethe locking ring 26- provided onthe member 18 engages all of the pins-21' on; the arms 20 of the cross-shaped driven :meimber 19, two. of which. rest against the inner surface of the locking ring and two against, the outer surface. The rotative movement'isimparted to the member 19 only when the diamond shaped. cam 18?- passes between the pins on the arms of the driven member; At each passage of the diamond-ashap'ed cam the member 19is turnedthrough, an angle of 90 degrees, the direction-of rotation of-the driving and driven members being the: same. Theicam 18 is note'xactly diamond shaped, but is so designed-that it will impart-an approximately uniform acceleration tothe driven member as oneof the pins 21' passes along from the forward-end ctr-the cam to the outermost angle thereof, after which a substantially uniform rotation is imparted to the driven-member as the pin! passes from the outermost angleof the cam to its rear extremity. During the period. of acceleration one of the pins passes through the rear passageway 2-7;between the cam and the ad jacent end of the locking ring 26 and during the period of rotation another pin passes through the forward passageway 27-. These passageways are of just suflicient width to permit the pasage of the pins, thus insuring quiet operation of the intermittent movement and preventing lost motion. Y

My improved intermittentgear is especially adaptable for moving picture machines because'of its uniform acceleration and retardation, also because of the efi'ective lock ng of the driven part during the mere r e- Pi tur machine must work at very high speedand any imperfect action results in,' 'ury tp thefragile and oft times very 'valudble film." The cam maybe shap to give y trat wt movement andrest. The longer the period of. rest relative tothe period of movement the better will be the projection. Obviously a gear which will permit'the greatest speed I claim as new and desire to secure by Let ters Patent,- is:

1. In a power transmitting mechanism, the combination of-a driving member, and a driven member, said driven member hav; ing a plurality ofspaced projections, said driving; member comprising a locking part adapted to pass between and simultaneously engage a plurality of the projections of said driven member and holdsaid driven member against movement anda driving cam adapted to -periodically engage said pro-v jections and partially rotate "said driven member, r3

'2, In el -power transmitting mechanism, the combination of a rotatable driving member and a driven member havinga plurality .ofspaced projections, said driving member comprising a driving part adapted to pcriodically engage.said-projections and partially rotate said driven member and alocking cam comprising an annular flange having arecessadjacent said driving cam, and adapted to pass between the projections of the driven member and simultaneously engage with its opposite edges, a plurality of said projections and hold the said driven its member against movement, during the in tervals between its movements as efiected bysaid dIlVIl'lg cam.

3. In a power transmitting mechanism,

the combination of a driving member, and

.against movement during the intervals between its intermittent operations.

4. In a power transmitting uiechz'mism said driven member and a locking cam for holdingsaid member against movement during the intervals between its intermittent operations.

5. In a power transmitting mechanism,

the combination of a driving member, and a driven member having a plurality of eccentrically disposed projections, said drivingmember comprising a locking ring or flange having a'recess or gap at one point in its circumference and a driving cam consisting of an axial projection located in the gap in said flange and adapted to successively engage the projections of said driven member for eflecting its partial rotation.

6. In a power transmitting mechanism, the combination of a driving member, and a driven member having a plurality of eccentrically disposed projectiona'said driving member comprising a locking ring or flange having a recess or gap at one point in its circumference and a driving cam an axial projection located in the gap said flange and adapted to pass within the circumference of said driven member and successively engage the projections of said driven member to effect its partial rotation, the ring thereafter engaging a plurality of said projections to hold the driven member against movement during the intervals between its intermittent o erations.

In testimony wnereo I have slgned'iny name hereto 1n the presence of wltnesses.

NICHOLAS POWER. Witnesses N. D. ALLING, L. W. ATWATER.

Genie: 01 this patent may be obtained for five cents each, by addressing the Commissioner of Iatenti, Washington, D. G. 

